I have a B-353 running on Win 7 on a netbook. While using a navigational program, OpnCPN the gps will drop out and gps function is lost. This even happens while using the ubiquitous termnial program Hyperterminal.

This is not an isolated incident and is the subject of an extensive thread(s) on Cruisers Forum. Everyone it seems that uses the BU-353 reports the same thing.

The navigation program OpnCPN drops out usually after 1 hour. Hyperterminal which is an old, old termimal program which sends and receives data from any selected com port drops out after 20 minutes to one hour.

When these applications stop receiving GPS data, the stream of NMEA sentances stops in Hyperterminal and the boat icon locks in OpnCpn. So there isn't any point in screen shots.

One difference though. In OpnCPN when it locks, the com port is gone in device manager. But in Hyperterminal it is still there but is not passing any sentances.

Have you installed the latest drivers for this device? If not, you need to uninstall the driver first. You can do this by going to Control Panel > Programs > select PL2303 > Uninstall. Once the driver is removed, turn off your computer and wait for a few minutes. Power up your computer and download this driver: (http://www.usglobalsat.com/store/download/62/windows_allinone_usb_driver_v130.zip). Make sure to extract the file and install the exe file.

Plug in the device and check the Device Manager. You can do this by right-clicking on Computer > Manage > Computer Management > System Tools > Device Manager > Ports (COM & LPT) > Prolific to USB Serial Comm Port (COMXX). Try to wiggle the device's cable around and see if it kept appearing and disappearing.

I installed the latest Prolific driver from their website a few weeks ago as part of the troubleshooting I have done. It is dated 3/12/2010. It didn't help.

I understand the one on your web site is a 2009 version and that is the one I had before installing the 2010 Prolific driver. It didn't work either.

I don't think that the connector is the problem. I can clearly hear a faint bell tone when I unplug and replug the connection. This doesn't happen in normal operation. The usb plug is solid and is making good contact.

When I do unplug it using GPSinfo I have to Close GPS and then Start GPS to get it running again.

Here is one other tidbit. When the GPS locks up using the navigation program OpnCPN, then it is impossible to reconnect without rebooting the PC. But when I unplug the GPS and replug it I can get it to work again simply by closing OpnCPN and restarting.

And here is another tidbit. When the GPS locks up with OpnCPN I close it. Then I open GPSinfo and hit start gps. Nothing happens. Then if I try to close GPSinfo it won't easily close. I have to hit the x icon several times and then the OS tells me that the program isn't responding and do I wish to close it. So I say yes.

So something is happening when the GPS locks up with OpnCPN that affects GPSinfo.

Here is one other tidbit. When the GPS locks up using the navigation program OpnCPN, then it is impossible to reconnect without rebooting the PC. But when I unplug the GPS and replug it I can get it to work again simply by closing OpnCPN and restarting.

David

Have you tried plugging in the device to different USB ports? Did you have the same problem? When it locks up, does the red light on the device still blink?

Does this also occur with another computer? Or this problem only happens with this one?

And here is another tidbit. When the GPS locks up with OpnCPN I close it. Then I open GPSinfo and hit start gps. Nothing happens. Then if I try to close GPSinfo it won't easily close. I have to hit the x icon several times and then the OS tells me that the program isn't responding and do I wish to close it. So I say yes.

So something is happening when the GPS locks up with OpnCPN that affects GPSinfo.

David

Keep in mind that you cannot use the GPSInfo and the OPnCPN at the same time. If you want to utilize both of the programs simultaneously, you can use a software called XPort. For more information on how to configure this, please click on the link: http://www.usglobalsat.com/forum/index.php?topic=1567.0

Also, can you set the buffers for the device's com port to 1? You can do this by going to your Device Manager and navigate to your Prolific Com Port. Right-click on it and select Properties. Go to Port Settings and press the Advanced button. Set the Receive and Transmit buffers to 1. Click OK and again.

One more thing, what is the firmware version of the device? In order to determine this, open up the GPSInfo utility. Select the proper com port and baud rate. Click on Start GPS. After a few seconds, press the Cold Start button. In the first few NMEA sentences, you should be able to see the version. It should look like something below:

I have reset the FIFO buffers to 1 (they were 14) and am now running the OpnCPN application to see what happens. Seems to me that this will worsen the problem.

I will report what happens in an hour or earlier if it locks up.

David

In a separate email, I will be sending you the current firmware along with the firmware update tool and instructions. Also, check your SPAM folder if you could not find it in your Inbox. Make sure to carefully read the instructions first.

Once you're done upgrading the firmware, can you please test it once more and see if you still encounter the same problem?